【Java工具类】替换字符串占位符{xxx}、${xxx}工具类

冷不防 2022-10-22 09:20 184阅读 0赞

import java.util.Map;
    import java.util.regex.Matcher;
    import java.util.regex.Pattern;
    
    public class StringTemplateUtil { 
        public static final String DEF_REGEX_1 = "\\{(.+?)\\}";
        public static final String DEF_REGEX_2 = "\\$\\{(.+?)\\}";
    
        public static String render(String template, Map<String, String> data) { 
            return render(template, data, DEF_REGEX_1);
        }
    
        public static String render(String template, Map<String, String> data, String regex) { 
            if (template == null || template.trim().isEmpty()) { 
                return "";
            }
    
            if (regex == null || regex.trim().isEmpty()) { 
                return template;
            }
    
            if (data == null || data.size() == 0) { 
                return template;
            }
    
            try { 
                StringBuffer appendReplaceSb = new StringBuffer();
                Pattern pattern = Pattern.compile(regex);
                Matcher matcher = pattern.matcher(template);
    
                while (matcher.find()) { 
                    // String currentStr = matcher.group(0);//整个正则匹配的字符串
                    String key = matcher.group(1);//当前第一个子分组正则匹配的字符串
                    String value = data.get(key);
    
                     /*Matcher. appendReplacement：将当前匹配的子字符串替换为指定的字符串，并且将替换后的字符串 及其之前到上次匹配的子字符串之后的字符串添加到一个StringBuffer对象中。*/
                    matcher.appendReplacement(appendReplaceSb, value);//
                }
    
    
                /* Matcher. appendTail：将最后一次匹配之后的字符串添加到一个StringBuffer对象中。*/
                matcher.appendTail(appendReplaceSb);
                return appendReplaceSb.toString();
            } catch (Exception e) { 
                e.printStackTrace();
            }
    
            return template;
        }
    }